MERCURY 87421 Oil Tank Gallon Cap 43298A2 43298A1 12335A1 V6 115 135 140 150

( Manufacturer Part Number: 87421 ), ( Part Type: Oil Hp Tank Cap ), ( Donor Motor: Loose )

Review MERCURY Oil Tank Gallon Cap V6 Only 115 135 140 150 Hp Yr Warranty

The **Mercury 43298A2/43298A1 12335A1 Oil Tank Gallon Cap** is a precision-engineered component designed specifically for select Mercury outboard motors, including models with V6 configurations producing horsepower ratings between **115 hp and 150 hp** across various model years. This high-quality oil tank cap is crafted to ensure optimal lubrication and engine performance while maintaining a secure, leak-proof seal under the demanding conditions of marine environments. Constructed from durable, corrosion-resistant materials, the cap is engineered to withstand the harsh effects of saltwater, UV exposure, and temperature fluctuations, which are common challenges faced by boaters in coastal and recreational settings. Its design features a **gallon measurement scale** etched directly onto the cap, allowing for easy and accurate oil level monitoring a critical factor in preventing engine wear and ensuring longevity. The cap is compatible with the **Mercury 87421** oil tank assembly, providing a tight, interference-fit seal that minimizes the risk of oil leaks, spills, or contamination. Whether installed on a **1990s-era V6 outboard** or a later model with similar specifications, this cap is a vital part of maintaining engine health, reducing maintenance downtime, and extending the life of the motor. Its straightforward yet reliable construction ensures that boaters can focus on their time on the water without worrying about mechanical failures tied to improper lubrication.

### **Pros and Cons of buying a Mercury 87421 43298A2 43298A1 12335A1 Oil Tank Gallon Cap (V6, 115 150 HP, Various Years)**

This part is a **gallon oil tank cap** designed for Mercury outboard motors, specifically for V6 engines ranging from **115 to 150 HP** across different model years (likely late 2000s to early 2010s). Below is a detailed breakdown of its advantages and drawbacks.

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### **Pros**

1. **Direct Fitment for Mercury V6 Outboards**

- The part is **engineered specifically for Mercury s V6 models**, ensuring compatibility with engines producing **115 150 HP**. This reduces the risk of leaks or improper sealing compared to generic or mismatched caps.

2. **Standard Gallon Capacity**

- A **one-gallon oil tank cap** is a common size for marine engines, making it convenient for routine oil changes. This size is practical for most recreational and mid-sized boats.

3. **Durable Material Construction**

- Mercury parts are typically made from **high-quality plastic or reinforced polymers**, designed to withstand marine environments, including UV exposure, saltwater corrosion, and temperature fluctuations.

4. **Easy Installation**

- Replacing an oil tank cap is a straightforward task that requires minimal tools (usually just a screwdriver or socket). The design is straightforward, reducing the likelihood of installation errors.

5. **Prevents Oil Contamination**

- A properly sealed oil cap ensures that **dirt, water, and debris** do not enter the oil tank, which helps maintain engine cleanliness and extends oil life.

6. **OEM Quality (Original Equipment Manufacturer)**

- Purchasing from Mercury (or an authorized dealer) means you re getting a part that meets the manufacturer s standards, reducing the risk of poor performance or failure.

7. **Compatibility with Multiple Model Years**

- The part appears to fit a range of **V6 engines from 2006 2013 (or similar years)**, making it a versatile choice if you re unsure of the exact model year.

8. **Reduces Oil Leaks**

- A well-fitting cap prevents oil from seeping out during operation, which is crucial for maintaining proper lubrication and avoiding engine damage.

9. **Part of Mercury s Warranty Network**

- If purchased from an authorized dealer, the part may still be covered under Mercury s warranty or return policies, providing peace of mind.

10. **Available from Reliable Sources**

- Mercury parts are widely available through **dealers, marine supply stores, and online retailers**, making it easy to source replacements.

---

### **Cons**

1. **Potential for Counterfeit Parts**

- Some aftermarket or third-party sellers may offer **fake or low-quality replicas** of Mercury parts. Buying from untrusted sources could result in a poorly fitted or failing cap.

2. **Limited Longevity in Harsh Conditions**

- While durable, **prolonged exposure to saltwater, extreme heat, or UV rays** can degrade plastic components over time. The cap may need replacement more frequently in aggressive marine environments.

3. **Price Consideration**

- As an **OEM part**, it may be **more expensive** than generic aftermarket alternatives. However, the trade-off is reliability and fitment.

4. **Stock Availability Issues**

- Depending on the model year and region, **parts may be discontinued**, leading to delays in ordering or higher costs for used/refurbished units.

5. **Potential for Misidentification**

- If the wrong part is purchased (e.g., confusing it with a **1.5-gallon or 2-gallon cap**), it may not fit properly, leading to leaks or installation difficulties.

6. **Replacement May Require Draining Oil**

- Some older Mercury engines require **draining the oil tank** before removing the cap, which can be inconvenient if you re in the middle of a trip.

7. **No Significant Performance Upgrade**

- Unlike some engine components, an oil tank cap is **functional rather than performance-oriented**. Replacing it won t improve horsepower or efficiency only reliability.

8. **Possible Wear Over Time**

- If the original cap was **damaged or worn**, a new one may still fail if the surrounding gasket or mounting area is degraded, requiring additional maintenance.

9. **Limited Customization Options**

- Unlike some engine components, oil tank caps are **standardized** you cannot modify them for better performance or aesthetics.

10. **Potential for Overpaying for New Parts**

- If the cap is **minorly damaged** (e.g., cracked but still functional), some may opt for a new part when a repair or alternative solution (like a gasket replacement) could suffice.

---

### **Conclusion**

The **Mercury 87421 43298A2 43298A1 12335A1 oil tank cap** is a **reliable, direct-fit replacement** for V6 outboard engines in the **115 150 HP range**, offering **proper sealing, durability, and compatibility** with OEM standards. Its **ease of installation and prevention of oil contamination** make it a practical choice for routine maintenance.

However, **potential downsides** such as **counterfeit risks, cost, stock availability issues, and environmental degradation** should be considered. If purchasing, **buying from an authorized dealer or reputable marine supplier** minimizes risks.

For most boat owners, **this is a worthwhile investment** if the cap is **genuine and properly fitted**, as it ensures **long-term engine protection**. If the cap is **already damaged or the engine is older**, evaluating whether a **new cap or gasket replacement** is the best solution is advisable.

---

### **Final Recommendation**

- **Buy from an authorized Mercury dealer or a trusted marine parts retailer** to ensure authenticity.

- **Verify compatibility** with your exact engine model and year before purchasing.

- **Consider aftermarket alternatives** (if available) if cost is a concern, but prioritize **OEM quality** for critical components like oil caps.

- **Replace the cap during routine maintenance** rather than waiting for failure to prevent oil leaks and contamination.

- **Inspect the surrounding gasket and mounting area** if degraded, address those issues simultaneously for a complete fix.

**Verdict:** **Highly recommended** for its **reliability, fitment, and role in preventing engine damage**, provided it is a **genuine Mercury part**.

Details:

Johnson and Eventide. Cowling Covers. Altman, IL 62411. The item you are looking at is guaranteed to be described, pictured, and cross-referenced correctly.

Fits V6 only, No cracks or breaks, Comes with cap, This part is sold a 1 year working warranty. Bargain Bin parts.

part #: 87421 prices

• $21.00-$89.95

specifications ouboaen:

• for makes: Mercury
• mpn: 87421
• part type: Oil Hp Tank Cap
• donor motor: Loose

general ouboaen:

• condition: Used
• Boat Parts > Outboard Engines Components > Other

shipping ouboaen:

• service: Standard
• transit: 2-6 Days
• cost: $0.00
• type: Fixed
• class: Standard

offer ouboaen:

• quantity: 1
• sold: 0
• availability: In Stock
• started: February 25, 2026
• options: Ship-to-home

payments ouboaen:

• credit card: Discover
• other
• wallet: Apple-pay

returns ouboaen:

• policy: No Returns

seller ouboaen:

• rating: 99.9%
• # reviews: 34174
• city: Altamont, Illinois

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